A recently discovered vulnerability, CVE-2020-26073, in Cisco SD-WAN vManage Software could potentially allow unauthenticated remote attackers to gain access to sensitive information. This comes as a result of the improper validation of directory traversal character sequences within requests to application programming interfaces (APIs). In this long-read post, we will discuss the details of the exploit, share code snippets and original references, and provide insight into the software updates released by Cisco to address this vulnerability.

Exploit Details

The crux of this vulnerability is that the application data endpoints of the affected Cisco SD-WAN vManage Software fail to properly validate directory traversal character sequences within the API requests. A malicious attacker can exploit this vulnerability by sending malicious requests to an API within the targeted application, leading to directory traversal attacks.

Upon conducting a successful exploit, the attacker gains access to sensitive information such as credentials and user tokens. The attacker can then use this information to further infiltrate the system and compromise additional data or services. It is crucial to note that there are no workarounds to address this vulnerability, and the only solution is to apply the software updates released by Cisco.

Example Code Snippet

To demonstrate the vulnerability, let's assume a typical API request in the vulnerable application may look like this:

GET /api/v1/data/{data} HTTP/1.1
Host: vulnerable_host

The attacker can manipulate the request to exploit directory traversal by modifying the {data} parameter:

GET /api/v1/data/../../../../../../../etc/passwd HTTP/1.1
Host: vulnerable_host

With this malicious request, the attacker can now access data in directories outside of the intended scope - in this case, the /etc/passwd file, which contains valuable information for further attacks.

Original References

Cisco has addressed the vulnerability in their security advisory and provided software updates to mitigate the issue. The official Cisco Security Advisory on CVE-2020-26073 can be found at the following link: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-vman-ageab9ck

The CVE-2020-26073 entry in the National Vulnerability Database can be accessed at this link: https://nvd.nist.gov/vuln/detail/CVE-2020-26073

Mitigation and Software Update

To protect against this vulnerability, Cisco has released software updates that address the identified issue. Administrators of Cisco SD-WAN vManage Software should review the Cisco Security Advisory and follow the recommended steps to download and apply the appropriate software updates. The advisory also provides guidance on determining whether the installed software is vulnerable and detailed instructions on obtaining and installing the necessary updates.

In summary, CVE-2020-26073 exposes a critical vulnerability in Cisco SD-WAN vManage Software, which could potentially allow remote attackers to gain unauthorized access to sensitive information. It is crucial for organizations dependent on Cisco SD-WAN vManage Software to apply the available software updates to mitigate the risk of exploitation. By staying informed and proactively taking action, system administrators can significantly reduce the chances of such attacks compromising their valuable data and resources.

Timeline

Published on: 11/18/2024 16:15:05 UTC
Last modified on: 11/18/2024 17:11:17 UTC